BACKGROUND: Serum ferritin is well known as a marker that is reflective of the iron storage status in blood. But only the hemoglobin level is generally included in the current selection criteria for blood donors. Recent studies have continuously shown that the serum ferritin levels are lower for the blood donors, and especially for women and repeat donors with a normal hemoglobin level. It has been suggested that serum ferritin should be included in the blood donor selection criteria. In this study, we examined the serum ferritin status in a Korean population, and we checked the validity of the recent related studies. METHODS: The hemoglobin and serum ferritin levels of the blood donors who visited Seoul National University Bundang Hospital were measured (total donors: 353, males: 252, females: 101). The hemoglobin levels were evaluated according to gender and the serum ferritin level, and the changes in the serum ferritin level were also checked for the repeat donors. RESULTS: The median serum ferritin level was 89.7 ng/mL (2.5~97.5%, 13.0~280.7 ng/mL). As classified by the serum ferritin levels, 9.9% of the males and 38.6% of the females showed low serum ferritin (< or =30 ng/mL) with a normal hemoglobin level. Among the 33 cases of repeat donors, 25 cases showed reduced serum ferritin changes (mean change: 17.4%). CONCLUSION: Similar to other recent studies, we found that the donors with normal hemoglobin could show a low serum ferritin level and especially the women and repeat donors in a Korean population. For the blood donors' safety, it is time to consider that the serum ferritin level should be included in the criteria for blood donor selection.
Blood Donors ; Female ; Ferritins ; Hemoglobins ; Humans ; Iron ; Male ; Patient Selection ; Tissue Donors

BACKGROUND: The hemoglobin A1c (HbA1c) level is widely used to monitor glycemic control in diabetes mellitus patients, and various methods are used for its determination. The CAPILLARYS 2 FLEX Piercing (Sebia) is a fully automated, high-throughput glycohemoglobin (HbA1c) analyzer based on capillary electrophoresis. METHODS: The analytical performance of the CAPILLARYS 2 FLEX Piercing analyzer was evaluated for its precision, linearity, correlation with the Variant II Turbo (Bio-Rad Laboratories, Inc.) analyzer, and its vulnerability to interference by carbamylated hemoglobin. We also investigated its agreement with National Glycohemoglobin Standardization Program (NGSP) targets. All evaluations were performed according to CLSI guidelines EP05, EP06, and EP09. RESULTS: The coefficients of variation (CVs) for within-run and total imprecision were 1.7% and 1.8% at low concentrations and 1.2% and 1.3% at high concentrations, respectively. Linearity was excellent, with R2=0.9882 in the range of 5.13-13.83%; these results highly correlated with those produced by Variant II Turbo (R2=0.9978). The 95% confidence interval (for differences from the NGSP target) was -0.3618-0.3343%. No significant interference of carbamylated hemoglobin was noted. CONCLUSIONS: The CAPILLARYS 2 FLEX Piercing analyzer showed excellent precision and linearity. Its results correlated with those obtained by the Variant II Turbo analyzer, and were agreement with the NGSP target. Therefore, its analytical performance is satisfactory for diabetes diagnosis and treatment monitoring.
Capillaries ; Diabetes Mellitus ; Electrophoresis, Capillary ; Hemoglobins ; Humans ; Organothiophosphorus Compounds

BACKGROUND: We evaluated the performance of multiplex tandem mass spectrometry (MS/MS) in newborn screening for detection of 6 lysosomal storage disorders (LSDs), namely, Niemann-Pick A/B, Krabbe, Gaucher, Fabry, and Pompe diseases and Hurler syndrome. METHODS: We revised the conditions and procedures of multiplex enzyme assay for the MS/MS analysis and determined the precision of our enzyme assay and the effects of sample amounts and incubation time on the results. We also measured the degree of correlation between the enzyme activities in the dried blood spots (DBSs) and those in the leukocytes. DBSs of 211 normal newborns and 13 newborns with various LSDs were analyzed using our revised methods. RESULTS: The intra- and inter-assay precisions were 2.9-18.7% and 8.1-18.1%, respectively. The amount of product obtained was proportional to the DBS eluate volume, but a slight flattening was observed in the product vs. sample volume curve at higher sample volumes. For each enzyme assay, the amount of product obtained increased linearly with the incubation period (range, 0-24 hr). Passing and Bablok regression analysis revealed that the enzyme activities in the DBSs and those in the leukocytes were favorably correlated. The enzyme activities measured in the DBSs were consistently lower in patients with LSDs than in normal newborns. CONCLUSIONS: The performance of our revised techniques for MS/MS detection and enzyme assays was of the generally acceptable standard. To our knowledge, this is the first report on the use of MS/MS for newborn screening of LSDs in an Asian population.
Dried Blood Spot Testing ; Enzyme Assays ; Enzymes/blood ; Humans ; Infant, Newborn ; Leukocytes/enzymology ; Lysosomal Storage Diseases/*diagnosis ; Republic of Korea ; Tandem Mass Spectrometry/*methods ; Time Factors

No abstract available.
Adult ; Cerebroside-Sulfatase/*metabolism ; Child, Preschool ; *Chromatography, High Pressure Liquid ; Enzyme Assays/instrumentation/*methods ; Female ; Humans ; Kinetics ; Leukocytes/*enzymology ; Leukodystrophy, Metachromatic/diagnosis/enzymology ; Male ; Middle Aged ; Reference Standards ; Substrate Specificity ; Sulfoglycosphingolipids/analysis/metabolism/standards ; *Tandem Mass Spectrometry/standards

BACKGROUND: Hemoglobin A1c (HbA1c) levels are widely used to monitor glycemic control in diabetes mellitus patients, and various methods are used for determining HbA1c levels. The ADAMS A1c HA-8180 (Arkray, Inc., Japan) is a fully automated HbA1c analyzer based on high-performance liquid chromatography (HPLC). METHODS: The analytical performance of the ADAMS A1c HA-8180 analyzer was evaluated on the basis of its precision, linearity, correlation with the Variant II Turbo (Bio-Rad Laboratories, USA), and agreement with the National Glycohemoglobin Standardization Program (NGSP) targets. All evaluations were performed according to Clinical and Laboratory Standard Institute (CLSI) guidelines EP05, EP06, and EP09. RESULTS: Coefficients of variation (CVs) for total precision at low and high levels were 0.99% and 1.16%, respectively. The linearity was excellent with R2 = 0.99 in the range of 4.98-15.10%. Its analytical performance was well correlated with that of Variant II Turbo (r = 0.9987). The 95% confidence interval of bias between the NGSP target and the levels measured using the ADAMS A1c HA-8180 was -0.402-0.225. CONCLUSIONS: The ADAMS A1c HA-8180 showed excellent precision, linearity, correlation with Variant II Turbo, and agreement with the NGSP target. Therefore, its analytical performance is satisfactory for diagnosis and treatment monitoring of diabetes.
Bias (Epidemiology) ; Chromatography, Liquid ; Diabetes Mellitus ; Hemoglobins ; Humans ; Organothiophosphorus Compounds

BACKGROUND: Molecular epidemiological typing of Neisseria gonorrhoeae is crucial for monitoring the spread of resistant strains. As reference strains can be used for laboratory internal quality control, we genetically characterised the American Type Culture Collection (ATCC) gonococcal strains by Neisseria gonorrhoeae multiantigen sequence typing (NG-MAST) and porB sequence typing using public multilocus sequence typing (PubMLST). METHODS: Eight ATCC gonococcal reference strains (ATCC 19424, ATCC 31426, ATCC 35541, ATCC 43069, ATCC 43070, ATCC 49226, ATCC 49926, and ATCC 49981) from Culti-Loops (Thermo Fisher Scientific, USA) were cultured. After DNA extraction, porB and tbpB were amplified and sequenced. Sequence types (STs) and allele numbers were each determined by NG-MAST (http://www.ng-mast.net) and porB sequence typing using PubMLST (http://pubmlst.org/neisseria/porB/). RESULTS: ATCC 19424 was identified as ST 266 by NG-MAST, and as Allele 946 by PubMLST. ATCC31426 was assigned a novel ST by NG-MAST, and was assigned Allele 958 with 1.2% mismatch by PubMLST. ATCC 35541 was identified as ST 12 by NG-MAST, and as Allele 624 by PubMLST. ATCC 43069 and ATCC 43070 were both identified as ST 681 by NG-MAST, and as Allele 984 by PubMLST. ATCC 49226 was identified as ST 1572 by NG-MAST, and as Allele 2110 by PubMLST. ATCC 49926 and ATCC 49981 were both identified as ST 16496 by NG-MAST, and as Allele 928 by PubMLST. CONCLUSIONS: The ST data obtained for ATCC gonococcal reference strains by NG-MAST and porB sequence typing using PubMLST can be used for quality assurance of molecular epidemiological typing in clinical microbiological laboratories.
Alleles ; DNA ; Multilocus Sequence Typing ; Neisseria gonorrhoeae ; Neisseria ; Quality Control

BACKGROUND: Tissues for transplantation can save lives or restore essential functions. According to national policies and regulations, access to suitable transplantation, as well as the level of safety, quality, efficacy of donation, and transplantation of tissues, differ significantly between countries. We reviewed a few guidelines on tissue banking from the aspect of screening tests. In addition, four-year experience with screening panels for donated bones and donors at a tertiary hospital is introduced. METHODS: Seven national and international guidelines for screening tests for donors and donated tissues were reviewed. At our institution, screening tests for donation involve two steps. At retrieval, the first screening panel, including ABO/Rh typing, unexpected antibody screening, VDRL, HBsAg, anti-HBs, anti-HBc IgM, anti-HCV, anti-HIV, and microbiological cultures was performed. The second screening panel, including the same tests, except culture studies, was performed after 90 days. From 2008 to 2011, a total of 245 retrievals of bone tissue were performed and the screening panel results were analyzed. RESULTS: Mandatory screening serologic tests for living donors can differ according to local law or regulation and/or screening for endemic diseases. At our institution, among 245 donated bones for a period of four years, 61 bone tissues were discarded due to noncompliance for the second screening (n=32), contamination or no culture study results (n=9), abnormal serologic test results (n=8), and so on. CONCLUSION: Donor screening policies for tissue banking are various according to national laws or endemic disease status. Second screening tests with consideration of the window period should be adopted.
Adoption ; Bone and Bones ; Donor Selection ; Endemic Diseases ; Hepatitis B Surface Antigens ; Humans ; Immunoglobulin M ; Jurisprudence ; Living Donors ; Mandatory Testing ; Mass Screening ; Serologic Tests ; Social Control, Formal ; Tertiary Care Centers ; Tissue Banks ; Tissue Donors ; Transplants

BACKGROUND: The Rh blood group includes several antigens, of which D, C, E, c, and e are clinically important. Although nucleic acids from whole blood can be used for Rh blood group genotyping, it is also possible to genotype free circulating fetal nucleic acids from plasma and serum. We performed Rh blood group phenotyping and genotyping using nucleic acids from whole blood and free circulating nucleic acids from plasma and serum, respectively. The results were compared. METHODS: Forty-four blood samples were phenotyped and genotyped for RhD and RhCE blood groups. Phenotyping was performed by hemagglutination assay. Further tests were performed on RhD-negative samples. Nucleic acids were extracted from whole blood, plasma, and serum. Plasma and serum were prepared after filtration and genotyped by real-time polymerase chain reaction. RESULTS: RhD blood group results showed one (2.3%) discrepant case in which the DEL phenotype appeared wild RHD genotype. Among nucleic acids, there were seven discrepant results: two from plasma and five from serum based on whole blood nucleic acids. RhCE blood group results showed three (6.8%) phenotype-genotype discordances. Among nucleic acids, seven (15.9%mpared to phenotypes. Kappa coefficients of serum were lower than those of plasma. CONCLUSION: RHD and RHCE genotype could be identified by assaying free circulating nucleic acids in plasma or serum. This study suggests that plasma is more reliable than serum as a specimen for RHD and RHCE genotyping of free circulating nucleic acids.
Blood Group Antigens ; Filtration ; Genotype ; Hemagglutination ; Nucleic Acids* ; Phenotype ; Plasma* ; Real-Time Polymerase Chain Reaction

As dried blood spots (DBSs) have various advantages over conventional venous blood sampling, some assays for detection of one or two anti-tuberculosis (TB) drugs in DBSs have been developed. However, there are no assays currently available for the simultaneous measurement of three or more anti-TB drugs in DBSs. In this study, we developed and evaluated a multiplex method for detecting nine anti-TB drugs including streptomycin, kanamycin, clarithromycin, cycloserine, moxifloxacin, levofloxacin, para-aminosalicylic acid, prothionamide, and linezolid in DBSs by using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Seventy-nine patient samples of DBS were analyzed on the UPLC-MS/MS system. All drug concentrations were determined within 4 min, and assay performance was evaluated. All drugs were clearly separated without ion suppression. Within-run and between-run precisions were 1.7-13.0% and 5.7-17.0%, respectively, at concentrations representing low and high levels for the nine drugs. Lower limits of detection and quantification were 0.06-0.6 and 0.5-5.0 µg/mL, respectively. Linearity was acceptable at five level concentrations for each drug. Correlations between drug concentrations in plasma and DBSs by using Passing-Bablock regression and Pearson's rho (ρ, 0.798-0.989) were acceptable. In conclusion, we developed a multiplex assay to measure nine second-line anti-TB drugs in DBSs successfully. This assay provided convenient and rapid drug quantification and could have applications in drug monitoring during treatment.
Antitubercular Agents/*blood ; Chromatography, High Pressure Liquid ; *Dried Blood Spot Testing ; Humans ; Limit of Detection ; Reproducibility of Results ; *Tandem Mass Spectrometry

Metachromatic leukodystrophy (MLD) is an autosomal recessive disease caused by a deficiency in arylsulfatase A (ARSA). However, decreased ARSA activity is also observed in pseudodeficiency (PD). To distinguish between MLD and PD, we performed gene mutation and sulfatide analyses by using dried blood spots (DBSs) from seven Korean individuals who underwent an analysis of ARSA activity. DNA was extracted from DBSs, and PCR-direct sequencing of ARSA was performed. The cDNA obtained was analyzed to confirm a novel mutation. Of the seven subjects, three were confirmed as having MLD, one was confirmed as having MLD-PD, one was confirmed as having PD, and the remaining two were obligate heterozygotes. We verified the novel pathogenic variant c.1107+1delG by performing familial and cDNA analyses. Sulfatide concentrations in DBSs were analyzed and were quantified by using ultra-performance liquid chromatography and tandem mass spectrometry, respectively. Total sulfatide concentration was inversely correlated with ARSA activity (Spearman's coefficient of rank correlation, P=0.929, P=0.0025). The results of this mutational and biochemical study on MLD will increase our understanding of the genetic characteristics of MLD in Koreans.
Cerebroside-Sulfatase ; Chromatography, Liquid ; DNA ; DNA, Complementary ; Heterozygote ; Leukodystrophy, Metachromatic* ; Tandem Mass Spectrometry